Planetary head forming tool

ABSTRACT

A tool for forming heads on rivets or the like. The tool includes cooperating internal and external gears and a driven shaft having an axis of rotation that is inclined relative to the axis of the driving shaft for establishing a planetary movement of the driven shaft as the drive shaft rotates. A head forming tool is carried by the driven shaft and is disposed at an angle to the axes of the driving and driven shafts. Due to this angular orientation the tool wipes across the surface of the rivet to work form this surface and upset it.

United StateS Patent 1 1 Mink [ Oct. 30, 1973 Inventor:

References Cited UNITED STATES PATENTS 11/1971 Ramseier 72/112 3/1965Bodmer 72/67 4/1969 Friedrich 72/67 2/1970 Silichev 72/67 8/1970Mareiniak ..72/406 4/1972 Ramseier ..72/126 Primary ExaminerChar1es W.Lanham Assistant Examiner-Gene Crosby Attorney-J. King Harness et al.

[57] ABSTRACT A tool for forming heads on rivets or the like. The toolincludes cooperating internal and external gears and a driven shafthaving an axis of rotation that is inclined relative to the axis of thedriving shaft for establishing a planetary movement of the driven shaftas the drive shaft rotates. A head forming tool is carried by the drivenshaft and is disposed at an angle to the axes of the driving and drivenshafts. Due to this angular orientation the tool wipes across thesurface of the rivet to work form this surface .and upset it.

5 Claims, 3 Drawing Figures PLANETARY HEAD FORMING TOOL BACKGROUND OFTHE INVENTION This invention relates to a head forming tool and moreparticularly to a tool for work forming heads on rivets or the like.

Tools have been proposed for forming heads on rivets by moving the headforming member in a planetary or wiping motion relative to the rivetshank to effect the upset. An example of such a tool is shown in U.S.Pat. No. 3,440,850 entitled Apparatus For Forming Locking Heads onRivets" issued on April 29, 1969 in the name of Karl Friedrich. The toolshown in that patent is expensive in that it requires several sphericalbearingsurfaces which must be accurately formed. The motion of thedriven tool forming element, however, has been found to provide anextremely good action.

It is, therefore, a principal object of this invention to provide animproved and simplified head forming tool.

It is another object of the invention to provide a head forming toolhaving a planetary wiping motion that is low in cost and efficient inoperation.

SUMMARY OF THE INVENTION A tool embodying this invention is adapted forforming heads on rivets or the like. The tool includes a drive shaftrotatable about a first axis and a driven shaft rotatable about a secondaxis, that is disposed at an angle to the first axis. Means establish adriving connection between the drive shaft and the driven shaft. A firstgear is affixed against rotation relative to the drive shaft and asecond gear is fixed for rotation with the driven shaft and is enmeshedwith the first gear. One of the gears is an internal gear and the othergear is an external gear for establishing a planetary motion of thedriven shaft upon rotation of the drive shaft. The driven shaft isadapted to carry a head forming tool for wiping and upsetting a rivet orthe like during its planetating motion.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross sectional view of ahead forming tool embodying this invention and is taken through the axisof the driving shaft.

FIG. 2 is a cross sectional view taken along the line 22 of FIG. 1.

FIG. 3 is a view showing the path of movement of a point on the headforming tool during operation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A head forming toolembodying this invention is identified generally by the referencenumeral 11. The tool 11 includes a stationary quill 12 in which a driveshaft 13 is journalled. The drive shaft 13 is rotatably driven about anaxis of rotation, indicated by the broken line 14, in any known manner.At the lower end of the drive shaft 13 an extension piece 15 isprovided. The extension piece 15 has an integral male threaded portion16 that is screwed into a tapped opening 17 formed in the drive shaft.

The extension 15 is formed with a bore 18 which bore is disposed at anangle to the drive shaft axis of rotation 14. The axis of the bore 18 isidentified by the broken line 19 in the drawings. An anti-frictionbearing 21 is pressed into the bore 18 and provides an opening 22 thatreceives a complementary extension 23 of a driven shaft or arbor,indicated generally by the reference numeral 24. The axis of the arbor24 coincides with the axis 19.

A fixed housing 25 is connected to the stationary quill 12 by aplurality of socket headed screws 26 (only one of which appears in thedrawings). The fixed housing 25 defines a cavity 27 in which theextension 15 is contained. A bore 28 intersects the cavity 27 and isdisposed coaxially with the drive shaft axis 14. A rotating housing 29has a cylindrical portion. 31 that extends through the bore 28. A flange32 of the housing 29 is disposed in the cavity 27 and is affixed to theextension 15 by means of socket headed screws or the like (not shown).

Abore 33 is formed in the housing 29 at an angle relative to the driveshaft angle 14 equal to the angle of the axis 19. Hence, the axis 19 maybe considered as the axis of the bore 33. Anti-friction bearings 34 arere ceived in the bore 33 and journal a cylindrical portion 35 of thedriven shaft or arbor 24. Hence, the arbor 24 is supported for rotationby the bearings 21 and 34 about the axis 19.

An external gear 36 is formed integrally with or is otherwise affixed tothe arbor 24. The external gear 36 is received within a complementarycounterbore 37 of the rotating housing 29. The counterbore 37 isdisposed relative to the housing 29 in such a way so that a portion ofthe teeth of the gear 36 extend through a side of the housing 29. Theseextending teeth mesh with the teeth of an internal gear 38. The internalgear 38 is fixed against rotation relative to the stationary housing 25in any known manner, as by means of socket headed screws (not shown).The arbor 24 has an enlarged cylindrical portion 39 defining adownwardly extending face or shoulder 41. Thrust bearings 42 areinterposed between the arbor shoulder 41 and a shoulder 43 formed on therotating housing 29.

The arbor 24 extends downwardly through an opening 44 formed in thelower face of the rotating housing 29 coaxially with the bore 33. Thisextending portion of the arbor 24 is formed with a tool receivingopening 45. The opening 45 is cylindrical in form and has an axisindicated by the broken line 46. The axis 46 is disposed at a smallerangle relative to the axis 19, three degrees being an appropriate angle.The axis 46 is, of-

course, angularly disposed relative to the axis 14 and the axes l4, l9and 46 all intersect at a common point 47.

A cylindrical shank 48 of a head forming tool having a forming surface49 is received within the opening 45. The head forming surface 49 isdefined at the end of a larger diameter portion 51 of the head formingtool. It will be noted that the point 47 lies upon the surface 49.

In operation as the drive shaft 13 rotates the driven shaft or arbor 24will trace a planetary path of motion. A point on the surface 49 of thehead forming tool will trace a path as shown in FIG. 3 and this motionmay be used to wipe and upset a rivet to form a locking head on therivet. This action occurs without any impacting of the forming toolsurface against the rivet and thus the tool 11 acts to form the upset ina substantially noiseless manner. This motion is accomplished withoutthe necessity of forming spherical bearing surfaces and all bearingsurfaces may be conveniently formed by conventional bearing operationsor the like.

It may be desirable to mount the head forming tool and particularly itscylindrical shank 48 within the 1. A tool for forming heads on rivets orthe like com- I prising a fixed housing, a drive shaft supported forrotation by said fixed housing about a first axis, a rotating housingfixed for rotation with said drive shaft, said rotating housing and saiddrive shaft defining a cavity, first and second spaced bearing meanscarried by said drive shaft and said rotating housing, a driven shaftrotatably supported in said spaced bearing means about a second axisangularly disposed relative to said first axis, an external gear affixedto said driven shaft within said cavity, an internal gear affixed tosaid fixed housing, said external gear being enmeshed with said internalgear for establishing a planetary motion of said driven shaft uponrotation of said drive shaft and means for affixing a head forming toolto said driven shaft.

2. A tool as set forth in claim 1 wherein the head forming tool issupported at an angle relative to the first and second axes.

3. A tool as set forth in claim 2 wherein the center of the head formingtool defines a third axis and the first, second and third axes allintersect at a common point.

4. A tool as set forth in claim 1 wherein the rotating housing is formedat an opening at one side thereof through which the external gearextends.

5. A tool as set forth in claim 4 wherein the first bearing meanscomprises an anti-friction bearing carried by the drive shaft and thesecond bearing means comprising an anti-friction bearing carried by therotating housing.

It t It

1. A tool for forming heads on rivets or the like comprising a fixed housing, a drive shaft supported for rotation by said fixed housing about a first axis, a rotating housing fixed for rotation with said drive shaft, said rotating housing and said drive shaft defining a cavity, first and second spaced bearing means carried by said drive shaft and said rotating housing, a driven shaft rotatably supported in said spaced bearing means about a second axis angularly disposed relative to said first axis, an external gear affixed to said driven shaft within said cavity, an internal gear affixed to said fixed housing, said external gear being enmeshed with said internal gear for establishing a planetary motion of said driven shaft upon rotation of said drive shaft and means for affixing a head forming tool to said driven shaft.
 2. A tool as set forth in claim 1 wherein the head forming tool is supported at an angle relative to the first and second axes.
 3. A tool as set forth in claim 2 wherein the center of the head forming tool defines a third axis and the first, second and third axes all intersect at a common point.
 4. A tool as set forth in claim 1 wherein the rotating housing is formed at an opening at one side thereof through which the external gear extends.
 5. A tool as set forth in claim 4 wherein the first bearing means comprises an anti-friction bearing carried by the drive shaft and the second bearing means comprising an anti-friction bearing carried by the rotating housing. 